Diesel engines with good fuel economy and power performance are widely used in various industries, such as motor vehicles, generator sets, ships, etc. However, particulate matter (PM) emissions from diesel engines have always been a concern. PM can remain suspended in the air for a long time, polluting the environment and affecting human physical and mental health. With the increasingly strict emission standards for diesel engines, diesel particulate filters (DPF) have become one of the essential technologies for diesel vehicle exhaust emissions to meet the standards. DPF design must consider functionality, performance, maintenance, and other aspects such as filtration efficiency, pressure drop loss, high temperature resistance, ash corrosion resistance, and cleaning mileage.

The adjacent honeycomb cells are alternately blocked at both ends, forcing the airflow to pass through the porous wall surface, and the particles are captured inside the wall surface and on the inlet wall surface, with a capture efficiency of over 90%. Since Peugeot Citroen began mass producing diesel cars equipped with DPF in 2000, the commercial application of DPF has a history of 15 years. Various oxide and non oxide materials are applied to DPF, and various structures of DPF have been developed. Due to the high temperature and corrosive exhaust gas in which DPF operates, DPF materials need to have excellent properties such as resistance to ash corrosion and thermal shock. In theory, materials with low thermal expansion coefficient and high thermal conductivity are most suitable for DPF applications, as high thermal conductivity ensures uniform temperature distribution during the regeneration process of DPF; The low thermal expansion coefficient helps to reduce the thermal stress caused by temperature gradients during DPF regeneration, thereby avoiding DPF cracking. The cleaning mileage is an important indicator that must be considered in DPF design. In order to extend the cleaning range of DPF, DPF often adopts a large inlet filtration volume design. For example, Ibiden Corporation in Japan uses a DPF with an octagonal inlet structure, Sumitomo Corporation in Japan uses an asymmetric hexagonal DPF structure, and Saint Gobain Corporation in France uses an asymmetric corrugated DPF structure. Various catalyst coating techniques are applied to DPF to reduce regeneration temperature, decrease particulate matter (PM) emissions, and reduce installation space size (SCR on DPF technology). The internal structure of DPF is also constantly changing to adapt to the development of new catalyst coating technologies.